Commit 23262cce authored by Niklas Cassel's avatar Niklas Cassel
Browse files

ata: libata-core: Remove support for decreasing the number of ports 



Commit f3187195 ("libata: separate out ata_host_alloc() and
ata_host_register()") added ata_host_alloc(), where the API allowed
a LLD to overallocate the number of ports supplied to ata_host_alloc(),
as long as the LLD decreased host->n_ports before calling
ata_host_register().

However, this functionally has never ever been used by a single LLD.

Because of the current API design, the assignment of ap->print_id is
deferred until registration time, which is bad, because that means that
the ata_port_*() print functions cannot be used by a LLD until after
registration time, which means that a LLD is forced to use a print
function that is non-port specific, even for a port specific error.

Remove the support for decreasing the number of ports, such that it will
be possible to assign ap->print_id earlier.

Reviewed-by: default avatarDamien Le Moal <dlemoal@kernel.org>
Reviewed-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240703184418.723066-14-cassel@kernel.org


Signed-off-by: default avatarNiklas Cassel <cassel@kernel.org>
parent 2199d6ff

drivers/ata/libata-core.c

+5 −17
Original line number Diff line number Diff line
@@ -5555,24 +5555,19 @@ EXPORT_SYMBOL_GPL(ata_host_put); 
/**

 *	ata_host_alloc - allocate and init basic ATA host resources

 *	@dev: generic device this host is associated with

 *	@max_ports: maximum number of ATA ports associated with this host

 *	@n_ports: the number of ATA ports associated with this host

 *

 *	Allocate and initialize basic ATA host resources.  LLD calls

 *	this function to allocate a host, initializes it fully and

 *	attaches it using ata_host_register().

 *

 *	@max_ports ports are allocated and host->n_ports is

 *	initialized to @max_ports.  The caller is allowed to decrease

 *	host->n_ports before calling ata_host_register().  The unused

 *	ports will be automatically freed on registration.

 *

 *	RETURNS:

 *	Allocate ATA host on success, NULL on failure.

 *

 *	LOCKING:

 *	Inherited from calling layer (may sleep).

 */

struct ata_host *ata_host_alloc(struct device *dev, int max_ports)

struct ata_host *ata_host_alloc(struct device *dev, int n_ports)

{

	struct ata_host *host;

	size_t sz;
@@ -5580,7 +5575,7 @@ struct ata_host *ata_host_alloc(struct device *dev, int max_ports) 
	void *dr;



	/* alloc a container for our list of ATA ports (buses) */

	sz = sizeof(struct ata_host) + (max_ports + 1) * sizeof(void *);

	sz = sizeof(struct ata_host) + n_ports * sizeof(void *);

	host = kzalloc(sz, GFP_KERNEL);

	if (!host)

		return NULL;
@@ -5600,11 +5595,11 @@ struct ata_host *ata_host_alloc(struct device *dev, int max_ports) 
	spin_lock_init(&host->lock);

	mutex_init(&host->eh_mutex);

	host->dev = dev;

	host->n_ports = max_ports;

	host->n_ports = n_ports;

	kref_init(&host->kref);



	/* allocate ports bound to this host */

	for (i = 0; i < max_ports; i++) {

	for (i = 0; i < n_ports; i++) {

		struct ata_port *ap;



		ap = ata_port_alloc(host);
@@ -5913,13 +5908,6 @@ int ata_host_register(struct ata_host *host, const struct scsi_host_template *sh 
		return -EINVAL;

	}



	/* Blow away unused ports.  This happens when LLD can't

	 * determine the exact number of ports to allocate at

	 * allocation time.

	 */

	for (i = host->n_ports; host->ports[i]; i++)

		ata_port_free(host->ports[i]);



	/* give ports names and add SCSI hosts */

	for (i = 0; i < host->n_ports; i++) {

		host->ports[i]->print_id = atomic_inc_return(&ata_print_id);

include/linux/libata.h

+1 −1
Original line number Diff line number Diff line
@@ -1069,7 +1069,7 @@ extern int sata_std_hardreset(struct ata_link *link, unsigned int *class, 
			      unsigned long deadline);

extern void ata_std_postreset(struct ata_link *link, unsigned int *classes);



extern struct ata_host *ata_host_alloc(struct device *dev, int max_ports);

extern struct ata_host *ata_host_alloc(struct device *dev, int n_ports);

extern struct ata_host *ata_host_alloc_pinfo(struct device *dev,

			const struct ata_port_info * const * ppi, int n_ports);

extern void ata_host_get(struct ata_host *host);